The present invention relates to spiropyran materials having the structure: ##STR2## wherein R.sub.1 is hydrogen or methyl; wherein R.sub.2, R.sub.3, R.sub.4, R.sub.5, R.sub.6 and R.sub.7 represents hydrogen or C.sub.1 -C.sub.5 lower alkyl; wherein when one of R.sub.2, R.sub.3, R.sub.4, R.sub.5, R.sub.6 or R.sub.7 is any of C.sub.2 -C.sub.5 lower alkyl, each of the other of the R.sub.2, R.sub.3, R.sub.4, R.sub.5, R.sub.6 and R.sub.7 moieties is hydrogen; wherein each of the dashed lines represents a carbon-carbon single bond or a carbon-carbon double bond, with at least one of the dashed lines being a carbon-carbon single bond, and uses thereof to augment or enhance the flavor and/or aroma of smoking tobacco.
There has been considerable work performed relating to substances which can be used to impart (or enhance) flavors to (or in) various consumable materials. These substances are used to diminish natural materials, some of which may be in short supply, and to provide more uniform properties in the finished product. Dill, basil, valerian oil-like, caraway seed-like, thyme-like, piney, raspberry-like, blackberry-like, camphoraceous, herbaceous, eucalyptol-like, cooling, minty, ionone, tea-like, floral, sweet, fruity, woody, apple-like, petitgrain-like, smokey, leafy and green flavor notes or combinations of these for improving the taste and aroma of artificial raspberry or other berry fruit flavoring compositions or tea flavor or synthetic "menthe oil" compositions are particularly desirable for many uses in consumable articles, e.g., foodstuffs. Green, floral, herbal, eucalyptol-like, sweet, minth and terpineol-like notes are particularly desirable in perfume compositions. Aromatic, sweet, minty and cooling notes are particularly desirable in tobacco.
Chemical compounds having the pyran ring are known to be useful in flavor and fragrance compositions. Thus, published Japanese application 7 4011-073 (Mar. 14, 1974) Mitshi Toatsu Chemicals Inc. discloses 2,5-diethyltetrhydropyran perfumes having rose-like perfume, and good stability in air, sunlight and humidity. Maltol, haing the generic name: 3-hydroxy-2-methyl(1,4-pyran) is disclosed in "Perfume and Flavor Chemicals," Arctander Vol. II, #1831, to have "a warm-fruity, caramellic-sweet odor with emphasis on the caraway note in the dry state". Saturated polycyclic ethers are disclosed in Chodroff, et al. U.S. Pat. No. 3,417,107 to have attractive ambergris notes as well as a high degree of persistence. The structures of such polycyclic ethers are as follows: ##STR3## The structures of the compounds in a mix of unsaturated compounds which are precursors of the Chodroff, et al. perfumery compounds are as follows: ##STR4## wherein one of the dashed lines represents a carbon-carbon double bond and the other of the dashed lines represents a single carbon.
U.S. Pat. No. 2,422,648 sets forth methods for producing a number of the compounds found to be useful in our invention thus, for example, examples III and IV at columns 6 and 7 of U.S. Pat. No. 2,422,648 are as follows: